<?php

namespace minga\framework;

/*
TbsZip version 2.16
Date: 2014-04-08
Author: Skrol29 (email: http://www.tinybutstrong.com/onlyyou.html)
Licence : LGPL
This class is independent from any other classes and has been originally created for the OpenTbs plug-in
for TinyButStrong Template Engine (TBS). OpenTbs makes TBS able to merge OpenOffice and Ms Office documents.
Visit http://www.tinybutstrong.com
 */

define('TBSZIP_DOWNLOAD', 1); // download (default)
define('TBSZIP_NOHEADER', 4); // option to use with DOWNLOAD: no header is sent
define('TBSZIP_FILE', 8); // output to file, or add from file
define('TBSZIP_STRING', 32); // output to string, or add from string

class clsTbsZip
{
	public $now = null;
	private $applyTimeOffset = true;
	public static $timeOffset = null;

	private $AddInfo;
	private $ArchFile;
	private $ArchHnd;
	private $ArchIsNew;
	private $ArchIsStream;
	private $CdEndPos;
	private $CdFileByName;
	private $CdFileLst;
	private $CdFileNbr;
	private $CdInfo;
	private $CdPos;
	private $DisplayError;
	// private $Error;
	// private $LastReadComp;
	// private $LastReadIdx;
	private $Meth8Ok;
	private $OutputHandle;
	private $OutputMode;
	private $OutputSrc;
	private $ReplByPos;
	private $ReplInfo;
	private $VisFileLst;

	public function __construct() {
		$this->Meth8Ok = extension_loaded('zlib'); // check if Zlib extension is available. This is need for compress and uncompress with method 8.
		$this->DisplayError = true;
		$this->ArchFile = '';
		// $this->Error = false;
	}

	public static function getTimeOffset()
	{
		if (self::$timeOffset == null)
			self::CalculateTimeOffset();
		return self::$timeOffset;
	}

	public static function CalculateTimeOffset() : void
	{
		$tmpzip2 = IO::GetTempFilename();
		$zip = new clsTbsZip();
		$zip->CreateNew();
		$zip->applyTimeOffset = false;
		$zip->FileAdd('a', "", TBSZIP_STRING);
		$zip->now = 1488375014;
		$zip->Flush(TBSZIP_FILE, $tmpzip2, "");
		$zip->Close();
		// averigua le offset
		$z2 = new \ZipArchive();
		$z2->open($tmpzip2);
		$stat = $z2->statIndex(0);
		$z2->close();
		$ti2 = (int)($stat['mtime']);
		self::$timeOffset = ($ti2 - $zip->now);
		IO::Delete($tmpzip2);
	}

	public function CreateNew($ArchName = 'new.zip') : void {
		// Create a new virtual empty archive, the name will be the default name when the archive is flushed.
		if (!isset($this->Meth8Ok))
			$this->__construct(); // for PHP 4 compatibility
		$this->Close(); // note that $this->ArchHnd is set to false here
		// $this->Error = false;
		$this->ArchFile = $ArchName;
		$this->ArchIsNew = true;
		$bin = 'PK' . chr(05) . chr(06) . str_repeat(chr(0), 18);
		$this->CdEndPos = strlen($bin) - 4;
		$this->CdInfo = ['disk_num_curr' => 0, 'disk_num_cd' => 0, 'file_nbr_curr' => 0, 'file_nbr_tot' => 0, 'l_cd' => 0, 'p_cd' => 0, 'l_comm' => 0, 'v_comm' => '', 'bin' => $bin];
		$this->CdPos = $this->CdInfo['p_cd'];
	}

	public function Open($ArchFile, $UseIncludePath = false) {
		// Open the zip archive
		if (!isset($this->Meth8Ok))
			$this->__construct(); // for PHP 4 compatibility
		$this->Close(); // close handle and init info
		// $this->Error = false;
		$this->ArchIsNew = false;
		$this->ArchIsStream = (is_resource($ArchFile) && (get_resource_type($ArchFile) == 'stream'));
		if ($this->ArchIsStream) {
			$this->ArchFile = 'from_stream.zip';
			$this->ArchHnd = $ArchFile;
		} else {
			// open the file
			$this->ArchFile = $ArchFile;
			$this->ArchHnd = fopen($ArchFile, 'rb', $UseIncludePath);
		}
		$ok = !($this->ArchHnd === false);
		if ($ok) $ok = $this->CentralDirRead();
		return $ok;
	}

	public function Close() : void {
		if (isset($this->ArchHnd) && ($this->ArchHnd !== false)) fclose($this->ArchHnd);
		$this->ArchFile = '';
		$this->ArchHnd = false;
		$this->CdInfo = [];
		$this->CdFileLst = [];
		$this->CdFileNbr = 0;
		$this->CdFileByName = [];
		$this->VisFileLst = [];
		$this->ArchCancelModif();
	}

	public function ArchCancelModif() : void {
		// $this->LastReadComp = false; // compression of the last read file (1=compressed, 0=stored not compressed, -1= stored compressed but read uncompressed)
		// $this->LastReadIdx = false; // index of the last file read
		$this->ReplInfo = [];
		$this->ReplByPos = [];
		$this->AddInfo = [];
	}

	public function FileAdd($Name, $Data, $DataType = TBSZIP_STRING, $Compress = true) {

		if ($Data === false)
			return $this->FileCancelModif($Name, false); // Cancel a previously added file

		// Save information for adding a new file into the archive
		$Diff = 30 + 46 + 2 * strlen($Name); // size of the header + cd info
		$Ref = $this->_DataCreateNewRef($Data, $DataType, $Compress, $Diff);
		if ($Ref === false)
			return false;
		$Ref['name'] = $Name;
		$this->AddInfo[] = $Ref;
		return $Ref['res'];

	}

	public function CentralDirRead() {
		$cd_info = 'PK' . chr(05) . chr(06); // signature of the Central Directory
		$cd_pos = -22;
		$this->_MoveTo($cd_pos, SEEK_END);
		$b = $this->_ReadData(4);
		if ($b === $cd_info) {
			$this->CdEndPos = ftell($this->ArchHnd) - 4;
		} else {
			$p = $this->_FindCDEnd($cd_info);
			//echo 'p='.var_export($p,true); exit;
			if ($p === false) {
				return $this->RaiseError('The End of Central Directory Record is not found.');
			}
				$this->CdEndPos = $p;
				$this->_MoveTo($p + 4);

		}
		$this->CdInfo = $this->CentralDirRead_End($cd_info);
		$this->CdFileLst = [];
		$this->CdFileNbr = $this->CdInfo['file_nbr_curr'];
		$this->CdPos = $this->CdInfo['p_cd'];

		if ($this->CdFileNbr <= 0)
			return $this->RaiseError('No header found in the Central Directory.');
		if ($this->CdPos <= 0)
			return $this->RaiseError('No position found for the Central Directory.');

		$this->_MoveTo($this->CdPos);
		for ($i = 0; $i < $this->CdFileNbr; $i++) {
			$x = $this->CentralDirRead_File($i);
			if ($x !== false) {
				$this->CdFileLst[$i] = $x;
				$this->CdFileByName[$x['v_name']] = $i;
			}
		}
		return true;
	}

	public function CentralDirRead_End($cd_info) {
		$b = $cd_info . $this->_ReadData(18);
		$x = [];
		$x['disk_num_curr'] = $this->_GetDec($b, 4, 2); // number of this disk
		$x['disk_num_cd'] = $this->_GetDec($b, 6, 2); // number of the disk with the start of the central directory
		$x['file_nbr_curr'] = $this->_GetDec($b, 8, 2); // total number of entries in the central directory on this disk
		$x['file_nbr_tot'] = $this->_GetDec($b, 10, 2); // total number of entries in the central directory
		$x['l_cd'] = $this->_GetDec($b, 12, 4); // size of the central directory
		$x['p_cd'] = $this->_GetDec($b, 16, 4); // position of start of central directory with respect to the starting disk number
		$x['l_comm'] = $this->_GetDec($b, 20, 2); // .ZIP file comment length
		$x['v_comm'] = $this->_ReadData($x['l_comm']); // .ZIP file comment
		$x['bin'] = $b . $x['v_comm'];
		return $x;
	}

	public function CentralDirRead_File($idx) {

		$b = $this->_ReadData(46);

		$x = $this->_GetHex($b, 0, 4);
		if ($x !== 'h:02014b50')
			return $this->RaiseError("Signature of Central Directory Header #" . $idx . " (file information) expected but not found at position " . $this->_TxtPos(ftell($this->ArchHnd) - 46) . ".");

		$x = [];
		$x['vers_used'] = $this->_GetDec($b, 4, 2);
		$x['vers_necess'] = $this->_GetDec($b, 6, 2);
		$x['purp'] = $this->_GetBin($b, 8, 2);
		$x['meth'] = $this->_GetDec($b, 10, 2);
		$x['time'] = $this->_GetDec($b, 12, 2);
		$x['date'] = $this->_GetDec($b, 14, 2);
		$x['crc32'] = $this->_GetDec($b, 16, 4);
		$x['l_data_c'] = $this->_GetDec($b, 20, 4);
		$x['l_data_u'] = $this->_GetDec($b, 24, 4);
		$x['l_name'] = $this->_GetDec($b, 28, 2);
		$x['l_fields'] = $this->_GetDec($b, 30, 2);
		$x['l_comm'] = $this->_GetDec($b, 32, 2);
		$x['disk_num'] = $this->_GetDec($b, 34, 2);
		$x['int_file_att'] = $this->_GetDec($b, 36, 2);
		$x['ext_file_att'] = $this->_GetDec($b, 38, 4);
		$x['p_loc'] = $this->_GetDec($b, 42, 4);
		$x['v_name'] = $this->_ReadData($x['l_name']);
		$x['v_fields'] = $this->_ReadData($x['l_fields']);
		$x['v_comm'] = $this->_ReadData($x['l_comm']);

		$x['bin'] = $b . $x['v_name'] . $x['v_fields'] . $x['v_comm'];

		return $x;
	}

	public function RaiseError($Msg) {
		if ($this->DisplayError) {
			if (PHP_SAPI === 'cli') {
				echo static::class . ' ERROR with the zip archive: ' . $Msg . "\r\n";
			} else {
				echo '<strong>' . static::class . ' ERROR with the zip archive:</strong> ' . $Msg . '<br>' . "\r\n";
			}
		}
		// $this->Error = $Msg;
		return false;
	}

	public function Debug($FileHeaders = false) : void {

		$this->DisplayError = true;

		if ($FileHeaders) {
			// Calculations first in order to have error messages before other information
			$idx = 0;
			$pos = 0;
			$pos_stop = $this->CdInfo['p_cd'];
			$this->_MoveTo($pos);
			while ($pos < $pos_stop && $this->_ReadFile($idx, false)) {
				$this->VisFileLst[$idx]['p_this_header (debug_mode only)'] = $pos;
				$pos = ftell($this->ArchHnd);
				$idx++;
			}
		}

		$nl = "\r\n";
		echo "<pre>";

		echo "-------------------------------" . $nl;
		echo "End of Central Directory record" . $nl;
		echo "-------------------------------" . $nl;
		print_r($this->DebugArray($this->CdInfo));

		echo $nl;
		echo "-------------------------" . $nl;
		echo "Central Directory headers" . $nl;
		echo "-------------------------" . $nl;
		print_r($this->DebugArray($this->CdFileLst));

		if ($FileHeaders) {
			echo $nl;
			echo "------------------" . $nl;
			echo "Local File headers" . $nl;
			echo "------------------" . $nl;
			print_r($this->DebugArray($this->VisFileLst));
		}

		echo "</pre>";

	}

	public function DebugArray($arr) {
		foreach ($arr as $k => $v) {
			if (is_array($v)) {
				$arr[$k] = $this->DebugArray($v);
			} elseif (substr($k, 0, 2) == 'p_') {
				$arr[$k] = $this->_TxtPos($v);
			}
		}
		return $arr;
	}

	public function FileExists($NameOrIdx) {
		return $this->FileGetIdx($NameOrIdx) !== false;
	}

	public function FileGetIdx($NameOrIdx) {
		// Check if a file name, or a file index exists in the Central Directory, and return its index
		if (is_string($NameOrIdx)) {
			if (isset($this->CdFileByName[$NameOrIdx])) {
				return $this->CdFileByName[$NameOrIdx];
			}
				return false;

		}
			if (isset($this->CdFileLst[$NameOrIdx])) {
				return $NameOrIdx;
			}
				return false;


	}

	public function FileGetIdxAdd($Name) {
		// Check if a file name exists in the list of file to add, and return its index
		if (!is_string($Name))
			return false;
		$idx_lst = array_keys($this->AddInfo);
		foreach ($idx_lst as $idx) {
			if ($this->AddInfo[$idx]['name'] === $Name)
				return $idx;
		}
		return false;
	}

	public function FileRead($NameOrIdx, $Uncompress = true) {

		// $this->LastReadComp = false; // means the file is not found
		// $this->LastReadIdx = false;

		$idx = $this->FileGetIdx($NameOrIdx);
		if ($idx === false)
			return $this->RaiseError('File "' . $NameOrIdx . '" is not found in the Central Directory.');

		$pos = $this->CdFileLst[$idx]['p_loc'];
		$this->_MoveTo($pos);

		// $this->LastReadIdx = $idx; // Can be usefull to get the idx

		$Data = $this->_ReadFile($idx, true);

		// Manage uncompression
		$Comp = 1; // means the contents stays compressed
		$meth = $this->CdFileLst[$idx]['meth'];
		if ($meth == 8) {
			if ($Uncompress) {
				if ($this->Meth8Ok) {
					$Data = gzinflate($Data);
					$Comp = -1; // means uncompressed
				} else {
					$this->RaiseError('Unable to uncompress file "' . $NameOrIdx . '" because extension Zlib is not installed.');
				}
			}
		} elseif($meth == 0) {
			$Comp = 0; // means stored without compression
		} else {
			if ($Uncompress)
				$this->RaiseError('Unable to uncompress file "' . $NameOrIdx . '" because it is compressed with method ' . $meth . '.');
		}
		// $this->LastReadComp = $Comp;

		return $Data;

	}

	public function _ReadFile($idx, $ReadData) {
		// read the file header (and maybe the data) in the archive, assuming the cursor in at a new file position

		$b = $this->_ReadData(30);

		$x = $this->_GetHex($b, 0, 4);
		if ($x !== 'h:04034b50')
			return $this->RaiseError("Signature of Local File Header #" . $idx . " (data section) expected but not found at position " . $this->_TxtPos(ftell($this->ArchHnd) - 30) . ".");

		$x = [];
		$x['vers'] = $this->_GetDec($b, 4, 2);
		$x['purp'] = $this->_GetBin($b, 6, 2);
		$x['meth'] = $this->_GetDec($b, 8, 2);
		$x['time'] = $this->_GetDec($b, 10, 2);
		$x['date'] = $this->_GetDec($b, 12, 2);
		$x['crc32'] = $this->_GetDec($b, 14, 4);
		$x['l_data_c'] = $this->_GetDec($b, 18, 4);
		$x['l_data_u'] = $this->_GetDec($b, 22, 4);
		$x['l_name'] = $this->_GetDec($b, 26, 2);
		$x['l_fields'] = $this->_GetDec($b, 28, 2);
		$x['v_name'] = $this->_ReadData($x['l_name']);
		$x['v_fields'] = $this->_ReadData($x['l_fields']);

		$x['bin'] = $b . $x['v_name'] . $x['v_fields'];

		// Read Data
		if (isset($this->CdFileLst[$idx])) {
			$len_cd = $this->CdFileLst[$idx]['l_data_c'];
			if ($x['l_data_c'] == 0) {
				// Sometimes, the size is not specified in the local information.
				$len = $len_cd;
			} else {
				$len = $x['l_data_c'];
				if ($len != $len_cd) {
					//echo "TbsZip Warning: Local information for file #".$idx." says len=".$len.", while Central Directory says len=".$len_cd.".";
				}
			}
		} else {
			$len = $x['l_data_c'];
			if ($len == 0) $this->RaiseError("File Data #" . $idx . " cannt be read because no length is specified in the Local File Header and its Central Directory information has not been found.");
		}

		$Data = null;
		if ($ReadData) {
			$Data = $this->_ReadData($len);
		} else {
			$this->_MoveTo($len, SEEK_CUR);
		}

		// Description information
		$desc_ok = ($x['purp'][2 + 3] == '1');
		if ($desc_ok) {
			$b = $this->_ReadData(12);
			$s = $this->_GetHex($b, 0, 4);
			$d = 0;
			// the specification says the signature may or may not be present
			if ($s == 'h:08074b50') {
				$b .= $this->_ReadData(4);
				$d = 4;
				$x['desc_bin'] = $b;
				$x['desc_sign'] = $s;
			} else {
				$x['desc_bin'] = $b;
			}
			$x['desc_crc32'] = $this->_GetDec($b, 0 + $d, 4);
			$x['desc_l_data_c'] = $this->_GetDec($b, 4 + $d, 4);
			$x['desc_l_data_u'] = $this->_GetDec($b, 8 + $d, 4);
		}

		// Save file info without the data
		$this->VisFileLst[$idx] = $x;

		// Return the info
		if ($ReadData) {
			return $Data;
		}
			return true;


	}

	public function FileReplace($NameOrIdx, $Data, $DataType = TBSZIP_STRING, $Compress = true) {
		// Store replacement information.

		$idx = $this->FileGetIdx($NameOrIdx);
		if ($idx === false)
			return $this->RaiseError('File "' . $NameOrIdx . '" is not found in the Central Directory.');

		$pos = $this->CdFileLst[$idx]['p_loc'];

		if ($Data === false) {
			// file to delete
			$this->ReplInfo[$idx] = false;
			$Result = true;
		} else {
			// file to replace
			$Diff = -$this->CdFileLst[$idx]['l_data_c'];
			$Ref = $this->_DataCreateNewRef($Data, $DataType, $Compress, $Diff);
			if ($Ref === false)
				return false;
			$this->ReplInfo[$idx] = $Ref;
			$Result = $Ref['res'];
		}

		$this->ReplByPos[$pos] = $idx;

		return $Result;

	}

	/**
	 * Return the state of the file.
	 *
	 * @return string|false
	 * 'u'=unchanged, 'm'=modified, 'd'=deleted, 'a'=added, false=unknown
	 */
	public function FileGetState($NameOrIdx) {

		$idx = $this->FileGetIdx($NameOrIdx);
		if ($idx === false) {
			$idx = $this->FileGetIdxAdd($NameOrIdx);
			if ($idx === false) {
				return false;
			}
				return 'a';

		} elseif (isset($this->ReplInfo[$idx])) {
			if ($this->ReplInfo[$idx] === false) {
				return 'd';
			}
				return 'm';

		}
			return 'u';


	}

	public function FileCancelModif($NameOrIdx, $ReplacedAndDeleted = true) {
		// cancel added, modified or deleted modifications on a file in the archive
		// return the number of cancels

		$nbr = 0;

		if ($ReplacedAndDeleted) {
			// replaced or deleted files
			$idx = $this->FileGetIdx($NameOrIdx);
			if ($idx !== false) {
				if (isset($this->ReplInfo[$idx])) {
					$pos = $this->CdFileLst[$idx]['p_loc'];
					unset($this->ReplByPos[$pos]);
					unset($this->ReplInfo[$idx]);
					$nbr++;
				}
			}
		}

		// added files
		$idx = $this->FileGetIdxAdd($NameOrIdx);
		if ($idx !== false) {
			unset($this->AddInfo[$idx]);
			$nbr++;
		}

		return $nbr;

	}

	public function Flush($Render = TBSZIP_DOWNLOAD, $File = '', $ContentType = '') {

		if (($File !== '') && ($this->ArchFile === $File) && ($Render == TBSZIP_FILE)) {
			$this->RaiseError('Method Flush() cannot overwrite the current opened archive: \'' . $File . '\''); // this makes corrupted zip archives without PHP error.
			return false;
		}
		if ($this->now == null)
			$now = time();
		else
			$now = $this->now;
		if ($this->applyTimeOffset)
			$now -= self::getTimeOffset();
		$ArchPos = 0;
		$Delta = 0;
		$FicNewPos = [];
		$DelLst = []; // idx of deleted files
		$DeltaCdLen = 0; // delta of the CD's size

		$date = $this->_MsDos_Date($now);
		$time = $this->_MsDos_Time($now);

		if (!$this->OutputOpen($Render, $File, $ContentType))
			return false;

		// output modified zipped files and unmodified zipped files that are beetween them
		ksort($this->ReplByPos);
		foreach ($this->ReplByPos as $ReplPos => $ReplIdx) {
			// output data from the zip archive which is before the data to replace
			$this->OutputFromArch($ArchPos, $ReplPos);
			// get current file information
			if (!isset($this->VisFileLst[$ReplIdx])) $this->_ReadFile($ReplIdx, false);
			$FileInfo = &$this->VisFileLst[$ReplIdx];
			$b1 = $FileInfo['bin'];
			if (isset($FileInfo['desc_bin'])) {
				$b2 = $FileInfo['desc_bin'];
			} else {
				$b2 = '';
			}
			$info_old_len = strlen($b1) + $this->CdFileLst[$ReplIdx]['l_data_c'] + strlen($b2); // $FileInfo['l_data_c'] may have a 0 value in some archives
			// get replacement information
			$ReplInfo = &$this->ReplInfo[$ReplIdx];
			if ($ReplInfo === false) {
				// The file is to be deleted
				$Delta = $Delta - $info_old_len; // headers and footers are also deleted
				$DelLst[$ReplIdx] = true;
			} else {
				// prepare the header of the current file
				$this->_DataPrepare($ReplInfo); // get data from external file if necessary
				$this->_PutDec($b1, $time, 10, 2); // time
				$this->_PutDec($b1, $date, 12, 2); // date
				$this->_PutDec($b1, $ReplInfo['crc32'], 14, 4); // crc32
				$this->_PutDec($b1, $ReplInfo['len_c'], 18, 4); // l_data_c
				$this->_PutDec($b1, $ReplInfo['len_u'], 22, 4); // l_data_u
				if ($ReplInfo['meth'] !== false) $this->_PutDec($b1, $ReplInfo['meth'], 8, 2); // meth
				// prepare the bottom description if the zipped file, if any
				if ($b2 !== '') {
					$d = (strlen($b2) == 16) ? 4 : 0; // offset because of the signature if any
					$this->_PutDec($b2, $ReplInfo['crc32'], $d + 0, 4); // crc32
					$this->_PutDec($b2, $ReplInfo['len_c'], $d + 4, 4); // l_data_c
					$this->_PutDec($b2, $ReplInfo['len_u'], $d + 8, 4); // l_data_u
				}
				// output data
				$this->OutputFromString($b1 . $ReplInfo['data'] . $b2);
				unset($ReplInfo['data']); // save PHP memory
				$Delta = $Delta + $ReplInfo['diff'] + $ReplInfo['len_c'];
			}
			// Update the delta of positions for zipped files which are physically after the currently replaced one
			for ($i = 0; $i < $this->CdFileNbr; $i++) {
				if ($this->CdFileLst[$i]['p_loc'] > $ReplPos) {
					$FicNewPos[$i] = $this->CdFileLst[$i]['p_loc'] + $Delta;
				}
			}
			// Update the current pos in the archive
			$ArchPos = $ReplPos + $info_old_len;
		}

		// Ouput all the zipped files that remain before the Central Directory listing
		if ($this->ArchHnd !== false) $this->OutputFromArch($ArchPos, $this->CdPos); // ArchHnd is false if CreateNew() has been called
		$ArchPos = $this->CdPos;

		// Output file to add
		$AddNbr = count($this->AddInfo);
		$AddDataLen = 0; // total len of added data (inlcuding file headers)
		$AddLst = [];
		if ($AddNbr > 0) {
			$AddPos = $ArchPos + $Delta; // position of the start
			$AddLst = array_keys($this->AddInfo);
			foreach ($AddLst as $idx) {
				$n = $this->_DataOuputAddedFile($idx, $AddPos);
				$AddPos += $n;
				$AddDataLen += $n;
			}
		}

		// Modifiy file information in the Central Directory for replaced files
		$b2 = '';
		$old_cd_len = 0;
		for ($i = 0; $i < $this->CdFileNbr; $i++) {
			$b1 = $this->CdFileLst[$i]['bin'];
			$old_cd_len += strlen($b1);
			if (!isset($DelLst[$i])) {
				if (isset($FicNewPos[$i])) $this->_PutDec($b1, $FicNewPos[$i], 42, 4); // p_loc
				if (isset($this->ReplInfo[$i])) {
					$ReplInfo = &$this->ReplInfo[$i];
					$this->_PutDec($b1, $time, 12, 2); // time
					$this->_PutDec($b1, $date, 14, 2); // date
					$this->_PutDec($b1, $ReplInfo['crc32'], 16, 4); // crc32
					$this->_PutDec($b1, $ReplInfo['len_c'], 20, 4); // l_data_c
					$this->_PutDec($b1, $ReplInfo['len_u'], 24, 4); // l_data_u
					if ($ReplInfo['meth'] !== false) $this->_PutDec($b1, $ReplInfo['meth'], 10, 2); // meth
				}
				$b2 .= $b1;
			}
		}
		$this->OutputFromString($b2);
		$ArchPos += $old_cd_len;
		$DeltaCdLen = $DeltaCdLen + strlen($b2) - $old_cd_len;

		// Output until "end of central directory record"
		if ($this->ArchHnd !== false) $this->OutputFromArch($ArchPos, $this->CdEndPos); // ArchHnd is false if CreateNew() has been called

		// Output file information of the Central Directory for added files
		if ($AddNbr > 0) {
			$b2 = '';
			foreach ($AddLst as $idx) {
				$b2 .= $this->AddInfo[$idx]['bin'];
			}
			$this->OutputFromString($b2);
			$DeltaCdLen += strlen($b2);
		}

		// Output "end of central directory record"
		$b2 = $this->CdInfo['bin'];
		$DelNbr = count($DelLst);
		if (($AddNbr > 0) || ($DelNbr > 0)) {
			// total number of entries in the central directory on this disk
			$n = $this->_GetDec($b2, 8, 2);
			$this->_PutDec($b2, $n + $AddNbr - $DelNbr, 8, 2);
			// total number of entries in the central directory
			$n = $this->_GetDec($b2, 10, 2);
			$this->_PutDec($b2, $n + $AddNbr - $DelNbr, 10, 2);
			// size of the central directory
			$n = $this->_GetDec($b2, 12, 4);
			$this->_PutDec($b2, $n + $DeltaCdLen, 12, 4);
			$Delta = $Delta + $AddDataLen;
		}
		$this->_PutDec($b2, $this->CdPos + $Delta, 16, 4); // p_cd (offset of start of central directory with respect to the starting disk number)
		$this->OutputFromString($b2);

		$this->OutputClose();

		return true;

	}

	// ----------------
	// output functions
	// ----------------

	public function OutputOpen($Render, $File, $ContentType) {

		if (($Render & TBSZIP_FILE) == TBSZIP_FILE) {
			$this->OutputMode = TBSZIP_FILE;
			if ('' . $File == '') $File = basename($this->ArchFile) . '.zip';
			$this->OutputHandle = @fopen($File, 'w');
			if ($this->OutputHandle === false) {
				return $this->RaiseError('Method Flush() cannot overwrite the target file \'' . $File . '\'. This may not be a valid file path or the file may be locked by another process or because of a denied permission.');
			}
		} elseif (($Render & TBSZIP_STRING) == TBSZIP_STRING) {
			$this->OutputMode = TBSZIP_STRING;
			$this->OutputSrc = '';
		} elseif (($Render & TBSZIP_DOWNLOAD) == TBSZIP_DOWNLOAD) {
			$this->OutputMode = TBSZIP_DOWNLOAD;
			// Output the file
			if ('' . $File == '') $File = basename($this->ArchFile);
			if (($Render & TBSZIP_NOHEADER) == TBSZIP_NOHEADER) {
			} else {
				header('Pragma: no-cache');
				if ($ContentType != '')
					header('Content-Type: ' . $ContentType);
				header('Content-Disposition: attachment; filename="' . $File . '"');
				header('Expires: 0');
				header('Cache-Control: must-revalidate, post-check=0, pre-check=0');
				header('Cache-Control: public');
				header('Content-Description: File Transfer');
				header('Content-Transfer-Encoding: binary');
				$Len = $this->_EstimateNewArchSize();
				if ($Len !== false)
					header('Content-Length: ' . $Len);
			}
		} else {
			return $this->RaiseError('Method Flush is called with a unsupported render option.');
		}

		return true;

	}

	public function OutputFromArch($pos, $pos_stop) : void {
		$len = $pos_stop - $pos;
		if ($len < 0)
			return;
		$this->_MoveTo($pos);
		$block = 1024;
		while ($len > 0) {
			$l = min($len, $block);
			$x = $this->_ReadData($l);
			$this->OutputFromString($x);
			$len = $len - $l;
		}
		unset($x);
	}

	public function OutputFromString($data) : void {
		if ($this->OutputMode === TBSZIP_DOWNLOAD) {
			echo $data; // donwload
		} elseif ($this->OutputMode === TBSZIP_STRING) {
			$this->OutputSrc .= $data; // to string
			// Esto estaba así en el código original:
			// } elseif (TBSZIP_FILE) {
			// Es siempre true y parece que es un error
			// y debería ser así:
			// } elseif ($this->OutputMode===TBSZIP_FILE) {
			// Pero como siempre funcionó así, quizás se
			// rompe algo así que lo dejo como true siempre
		} else {
			fwrite($this->OutputHandle, $data); // to file
		}
	}

	public function OutputClose() : void {
		if (($this->OutputMode === TBSZIP_FILE) && ($this->OutputHandle !== false)) {
			fclose($this->OutputHandle);
			$this->OutputHandle = false;
		}
	}

	// ----------------
	// Reading functions
	// ----------------

	public function _MoveTo($pos, $relative = SEEK_SET) : void {
		fseek($this->ArchHnd, $pos, $relative);
	}

	public function _ReadData($len) {
		if ($len > 0) {
			return fread($this->ArchHnd, $len);
		}
			return '';

	}

	// ----------------
	// Take info from binary data
	// ----------------

	public function _GetDec($txt, $pos, $len) {
		$x = substr($txt, $pos, $len);
		$z = 0;
		for ($i = 0; $i < $len; $i++) {
			$asc = ord($x[$i]);
			if ($asc > 0) $z = $z + $asc * pow(256, $i);
		}
		return $z;
	}

	public function _GetHex($txt, $pos, $len) {
		$x = substr($txt, $pos, $len);
		return 'h:' . bin2hex(strrev($x));
	}

	public function _GetBin($txt, $pos, $len) {
		$x = substr($txt, $pos, $len);
		$z = '';
		for ($i = 0; $i < $len; $i++) {
			$asc = ord($x[$i]);
			if (isset($x[$i])) {
				for ($j = 0; $j < 8; $j++) {
					$z .= ($asc & pow(2, $j)) ? '1' : '0';
				}
			} else {
				$z .= '00000000';
			}
		}
		return 'b:' . $z;
	}

	// ----------------
	// Put info into binary data
	// ----------------

	public function _PutDec(&$txt, $val, $pos, $len) : void {
		$x = '';
		for ($i = 0; $i < $len; $i++) {
			if ($val == 0) {
				$z = 0;
			} else {
				$z = (int)($val % 256);
				if (($val < 0) && ($z != 0)) { // ($z!=0) is very important, example: val=-420085702
					// special opration for negative value. If the number id too big, PHP stores it into a signed integer. For example: crc32('coucou') => -256185401 instead of 4038781895. NegVal = BigVal - (MaxVal+1) = BigVal - 256^4
					$val = ($val - $z) / 256 - 1;
					$z = 256 + $z;
				} else {
					$val = ($val - $z) / 256;
				}
			}
			$x .= chr($z);
		}
		$txt = substr_replace($txt, $x, $pos, $len);
	}

	public function _MsDos_Date($Timestamp = false) {
		// convert a date-time timstamp into the MS-Dos format
		$d = ($Timestamp === false) ? getdate() : getdate($Timestamp);
		return (($d['year'] - 1980) * 512) + ($d['mon'] * 32) + $d['mday'];
	}

	public function _MsDos_Time($Timestamp = false) {
		// convert a date-time timstamp into the MS-Dos format
		$d = getdate($Timestamp);
		return ($d['hours'] * 2048) + ($d['minutes'] * 32) + (int)($d['seconds'] / 2); // seconds are rounded to an even number in order to save 1 bit
	}

	public function _MsDos_Debug($date, $time) {
		// Display the formated date and time. Just for debug purpose.
		// date end time are encoded on 16 bits (2 bytes) : date = yyyyyyymmmmddddd , time = hhhhhnnnnnssssss
		$y = ($date & 65024) / 512 + 1980;
		$m = ($date & 480) / 32;
		$d = ($date & 31);
		$h = ($time & 63488) / 2048;
		$i = ($time & 1984) / 32;
		$s = ($time & 31) * 2; // seconds have been rounded to an even number in order to save 1 bit
		return $y . '-' . str_pad((string)$m, 2, '0', STR_PAD_LEFT) . '-'
			. str_pad((string)$d, 2, '0', STR_PAD_LEFT) . ' '
			. str_pad((string)$h, 2, '0', STR_PAD_LEFT) . ':'
			. str_pad((string)$i, 2, '0', STR_PAD_LEFT) . ':'
			. str_pad((string)$s, 2, '0', STR_PAD_LEFT);
	}

	public function _TxtPos($pos) {
		// Return the human readable position in both decimal and hexa
		return $pos . " (h:" . dechex($pos) . ")";
	}

	/**
	 * Search the record of end of the Central Directory.
	 * Return the position of the record in the file.
	 * Return false if the record is not found. The comment cannot exceed 65335 bytes (=FFFF).
	 * The method is read backwards a block of 256 bytes and search the key in this block.
	 */
	public function _FindCDEnd($cd_info) {
		$nbr = 1;
		$p = false;
		$pos = ftell($this->ArchHnd) - 4 - 256;
		while ($nbr < 256) {
			if ($pos <= 0) {
				$pos = 0;
				$nbr = 256; // in order to make this a last check
			}
			$this->_MoveTo($pos);
			$x = $this->_ReadData(256);
			$p = strpos($x, $cd_info);
			if ($p === false) {
				$nbr++;
				$pos = $pos - 256 - 256;
			} else {
				return $pos + $p;
			}
		}
		return false;
	}

	public function _DataOuputAddedFile($Idx, $PosLoc) {

		$Ref = &$this->AddInfo[$Idx];
		$this->_DataPrepare($Ref); // get data from external file if necessary

		// Other info
		if ($this->now == null)
			$now = time();
		else
			$now = $this->now;
		if ($this->applyTimeOffset)
			$now -= self::getTimeOffset();

		$date = $this->_MsDos_Date($now);
		$time = $this->_MsDos_Time($now);
		$len_n = strlen($Ref['name']);
		$purp = 2048; // purpose // +8 to indicates that there is an extended local header

		// Header for file in the data section
		$b = 'PK' . chr(03) . chr(04) . str_repeat(' ', 26); // signature
		$this->_PutDec($b, 20, 4, 2); //vers = 20
		$this->_PutDec($b, $purp, 6, 2); // purp
		$this->_PutDec($b, $Ref['meth'], 8, 2); // meth
		$this->_PutDec($b, $time, 10, 2); // time
		$this->_PutDec($b, $date, 12, 2); // date
		$this->_PutDec($b, $Ref['crc32'], 14, 4); // crc32
		$this->_PutDec($b, $Ref['len_c'], 18, 4); // l_data_c
		$this->_PutDec($b, $Ref['len_u'], 22, 4); // l_data_u
		$this->_PutDec($b, $len_n, 26, 2); // l_name
		$this->_PutDec($b, 0, 28, 2); // l_fields
		$b .= $Ref['name']; // name
		$b .= ''; // fields

		// Output the data
		$this->OutputFromString($b . $Ref['data']);
		$OutputLen = strlen($b) + $Ref['len_c']; // new position of the cursor
		unset($Ref['data']); // save PHP memory

		// Information for file in the Central Directory
		$b = 'PK' . chr(01) . chr(02) . str_repeat(' ', 42); // signature
		$this->_PutDec($b, 20, 4, 2); // vers_used = 20
		$this->_PutDec($b, 20, 6, 2); // vers_necess = 20
		$this->_PutDec($b, $purp, 8, 2); // purp
		$this->_PutDec($b, $Ref['meth'], 10, 2); // meth
		$this->_PutDec($b, $time, 12, 2); // time
		$this->_PutDec($b, $date, 14, 2); // date
		$this->_PutDec($b, $Ref['crc32'], 16, 4); // crc32
		$this->_PutDec($b, $Ref['len_c'], 20, 4); // l_data_c
		$this->_PutDec($b, $Ref['len_u'], 24, 4); // l_data_u
		$this->_PutDec($b, $len_n, 28, 2); // l_name
		$this->_PutDec($b, 0, 30, 2); // l_fields
		$this->_PutDec($b, 0, 32, 2); // l_comm
		$this->_PutDec($b, 0, 34, 2); // disk_num
		$this->_PutDec($b, 0, 36, 2); // int_file_att
		$this->_PutDec($b, 0, 38, 4); // ext_file_att
		$this->_PutDec($b, $PosLoc, 42, 4); // p_loc
		$b .= $Ref['name']; // v_name
		$b .= ''; // v_fields
		$b .= ''; // v_comm

		$Ref['bin'] = $b;

		return $OutputLen;

	}

	public function _DataCreateNewRef($Data, $DataType, $Compress, $Diff) {

		if (is_array($Compress)) {
			$result = 2;
			$meth = $Compress['meth'];
			$len_u = $Compress['len_u'];
			$crc32 = $Compress['crc32'];
			$Compress = false;
		} elseif ($Compress && ($this->Meth8Ok)) {
			$result = 1;
			$meth = 8;
			$len_u = false; // means unknown
			$crc32 = false;
		} else {
			$result = ($Compress) ? -1 : 0;
			$meth = 0;
			$len_u = false;
			$crc32 = false;
			$Compress = false;
		}

		if ($DataType == TBSZIP_STRING) {
			$path = false;
			if ($Compress) {
				// we compress now in order to save PHP memory
				$len_u = strlen($Data);
				$crc32 = crc32($Data);
				$Data = gzdeflate($Data);
				$len_c = strlen($Data);
			} else {
				$len_c = strlen($Data);
				if ($len_u === false) {
					$len_u = $len_c;
					$crc32 = crc32($Data);
				}
			}
		} else {
			$path = $Data;
			$Data = false;
			if (file_exists($path)) {
				$fz = filesize($path);
				if ($len_u === false) $len_u = $fz;
				$len_c = ($Compress) ? false : $fz;
			} else {
				return $this->RaiseError("Cannot add the file '" . $path . "' because it is not found.");
			}
		}

		// at this step $Data and $crc32 can be false only in case of external file, and $len_c is false only in case of external file to compress
		return ['data' => $Data, 'path' => $path, 'meth' => $meth, 'len_u' => $len_u, 'len_c' => $len_c, 'crc32' => $crc32, 'diff' => $Diff, 'res' => $result];

	}

	private function _DataPrepare(&$Ref) : void
	{
		// returns the real size of data
		if ($Ref['path'] !== false)
		{
			$Ref['data'] = file_get_contents($Ref['path']);
			if ($Ref['crc32'] === false)
				$Ref['crc32'] = crc32($Ref['data']);
			if ($Ref['len_c'] === false)
			{
				// means the data must be compressed
				$Ref['data'] = gzdeflate($Ref['data']);
				$Ref['len_c'] = strlen($Ref['data']);
			}
		}
	}

	public function _EstimateNewArchSize($Optim = true) {
		// Return the size of the new archive, or false if it cannot be calculated (because of external file that must be compressed before to be insered)
		if ($this->ArchIsNew) {
			$Len = strlen($this->CdInfo['bin']);
		} elseif ($this->ArchIsStream) {
			$x = fstat($this->ArchHnd);
			$Len = $x['size'];
		} else {
			$Len = filesize($this->ArchFile);
		}

		// files to replace or delete
		foreach ($this->ReplByPos as $i) {
			$Ref = &$this->ReplInfo[$i];
			if ($Ref === false) {
				// file to delete
				$Info = &$this->CdFileLst[$i];
				if (!isset($this->VisFileLst[$i])) {
					if ($Optim)
						return false; // if $Optimization is set to true, then we d'ont rewind to read information
					$this->_MoveTo($Info['p_loc']);
					$this->_ReadFile($i, false);
				}
				$Vis = &$this->VisFileLst[$i];
				$Len += -strlen($Vis['bin']) - strlen($Info['bin']) - $Info['l_data_c'];
				if (isset($Vis['desc_bin'])) $Len += -strlen($Vis['desc_bin']);
			} elseif ($Ref['len_c'] === false) {
				return false; // information not yet known
			} else {
				// file to replace
				$Len += $Ref['len_c'] + $Ref['diff'];
			}
		}

		// files to add
		$i_lst = array_keys($this->AddInfo);
		foreach ($i_lst as $i) {
			$Ref = &$this->AddInfo[$i];
			if ($Ref['len_c'] === false) {
				return false; // information not yet known
			}
				$Len += $Ref['len_c'] + $Ref['diff'];

		}

		return $Len;

	}
}
